A team of U.K. scientists has discovered a giant valley beneath the ice of the Antarctic that is deeper than the Grand Canyon.

According to a press release, the researchers were investigating and mapping a West Antarctica region when they discovered the valley. Lying beneath the ice, it is three kilometers deep, 300 kilometers long and 25 kilometers across.

The team made up of scientists from the British Antarctic Survey, Newcastle University and the universities of Bristol, Edinburgh, Exeter and York. Their mission was to map the Ellsworth Subglacial Highlands using satellite and ice-penetrating radar data.

Their study was published in the journal Geological Society of America Bulletin.

"While the idea of West Antarctic Ice Sheet growth and decay over the past few million years has been discussed for decades, the precise location where the ice sheet may originate from in growth phases, and decay back to in periods of decay, has not been known," Martin Siegert, a geosciences professor at Bristol, said in the release.

The research team found the ancient valley and mountain range to have been formed millions of years ago by a small ice field, such as the ones of the Antarctic Peninsula, Arctic Canada or Alaska.

"By looking at the topography beneath the ice sheet using a combination of ice-penetrating radio-echo sounding and satellite imagery, we have revealed a region which possesses classic glacial geomorphic landforms, such as u-shaped valleys and cirques, that could only have been formed by a small ice cap, similar to those seen at present in the Canadian and Russian High Arctic," said Siegert. "The region uncovered is, therefore, the site of ice sheet genesis in West Antarctica."

Study lead author Dr. Neil Ross, of Newcastle, said the team's analysis will help future studies understand ancient ice fields.

"The discovery of this huge trough, and the characterization of the surrounding mountainous landscape, was incredibly serendipitous," he said in the release. "We had acquired ice penetrating radar data from both ends of this huge hidden valley, but we had no information to tell us what was in between. Satellite data was used to fill the gap, because despite being covered beneath several kilometers of ice, the valley is so vast that it can be seen from space.

"To me, this just goes to demonstrate how little we still know about the surface of our own planet. The discovery and exploration of hidden, previously-unknown landscapes is still possible and incredibly exciting, even now."